code: def test_image_nodata(self):
      img = Image(
          ([1, 2, 3], [0, 1], np.array([[0, 1, 2], [2, 3, 4]]))
      ).opts(nodata=0)
      state = self._get_plot_state(img)
      self.assertEqual(state["data"][0]["type"], "heatmap")
      self.assertEqual(
          state["data"][0]["z"], np.array([[np.nan, 1, 2], [2, 3, 4]])
      )
  
file_path: holoviews/holoviews/tests/plotting/plotly/test_imageplot.py
imports: import numpy
  from holoviews.element import Image
  from .test_plot import TestPlotlyPlot
label_desc: Use image node_id 2 for calling the TestImagePlot obj's underlying member method code with example usage: obj.test_image_nodata() without return types